✨📕 The NEWThe NEW Collegiate Dictionary, 12th Edition Over 5,000 words added — Buy Now! Collegiate DictionaryBuy Now!

trillion

noun

tril·​lion ˈtri(l)-yən How to pronounce trillion (audio)
1
: a number equal to 1,000 times one billion see Table of Numbers
2
: an indeterminately large number
a trillion mosquitoes out tonight
trillion adjective
trillionth adjective or noun

Examples of trillion in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Think of your gut as an ecosystem with a large community of trillions of microorganisms. Caitlin Pagán, Verywell Health, 24 Nov. 2025 Nuclear weapons cost trillions of dollars. John Seiler, Oc Register, 23 Nov. 2025 Trump officials have pointed to forecasts showing trillions in tariff revenue over the next decade to bolster their case, but several wild-card factors could significantly diminish or wipe out those predictions entirely. Ramsey Touchberry, The Washington Examiner, 21 Nov. 2025 Amazingly, the exocomets, which formed around an alien star trillions of kilometers away from us, looked downright familiar. Phil Plait, Scientific American, 20 Nov. 2025 See All Example Sentences for trillion

Word History

Etymology

French, from tri- + -illion (as in million)

First Known Use

1745, in the meaning defined at sense 2

Time Traveler
The first known use of trillion was in 1745

Browse Nearby Words

Cite this Entry

“Trillion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/trillion. Accessed 27 Nov. 2025.

Kids Definition

trillion

noun
tril·​lion ˈtril-yən How to pronounce trillion (audio)
1
: a number equal to 1,000 times one billion see number
2
: a very large number
a trillion mosquitoes out tonight
trillion adjective
trillionth adjective
trillionth noun

More from Merriam-Webster on trillion

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!